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四川盆地东北部晚二叠世孤立碳酸盐台地边缘生物礁岩中发育的放射轴状纤维状胶结物(RFC),虽然已完全白云石化,但仍然具有双晶面弯曲(波状消光)且远端收敛的特征,高锶、高钠和暗阴极发光等反映海源流体环境的地球化学特征以及层状胶结物和内部沉积物等RFC的其它特征。RFC的原始矿物是海水环境中沉淀的高镁方解石,其存在说明四川盆地东北部二叠系长兴组海绵礁发育于陡峭的台地边缘,并具有千万年尺度的长期与海水接触的地质条件。RFC中内部沉积物的存在说明胶结过程持续时间很长并有短时间的间断,虽然这种间断与短时间的海平面下降有关,但就RFC发育的整个千万年尺度的时间来说,海平面是上升的,生物礁的建造速度与海平面上升幅度基本一致。
Radial-axial fibrous cement (RFC), developed in the late Permian marginal reef rocks of the Northeastern Sichuan Basin, is fully dolomitized but still exhibits bimodal curvature (wave-like extinction) and far End convergence, high strontium, high sodium and dark cathodoluminescence and other geochemical characteristics of the environment reflect the source of the sea environment and layered cement and internal sediment and other characteristics of the RFC. The original minerals of RFC are high magnesium calcite precipitated in seawater environment. The existence of these rocks indicates that the sponge reef of Changxing Formation of Permian in the northeastern Sichuan Basin developed on the steep platform margin and has long-term geological conditions of tens of millions of years of contact with seawater. The existence of internal sediments in the RFC suggests that the cementing process lasts long and breaks down for a short period of time. Although this discontinuity is related to the short-term sea-level decline, for the entire 10,000-million-year period of RFC development, Plane is up, the reef construction speed and sea level rise basically the same.